Carbon materials etc. that store and release lithium are currently being used as electrodes for lithium batteries, though, since their redox potentials are lower than the reduction potential of the electrolytic solution, there is a possibility that the electrolytic solution will degrade. Accordingly, lithium titanate which has a redox potential higher than the reduction potential of the electrolytic solution is under consideration, but lithium titanate has a problem of low output property. Meanwhile, there is an attempt to nanosize lithium titanate to improve output property. However, reducing the carbon content in a composite material of lithium titanate nanoparticles and carbon is challenging, and improving the capacitance property was difficult.
Accordingly, a method of obtaining dispersed lithium titanate supported on carbon by applying shear stress and centrifugal force to the reactant in a rotating reactor to promote chemical reaction (generally referred to as a mechanochemical reaction) is known (see e.g. Patent Documents 1 and 2).
The object of the conventional method employing this mechanochemical reaction is to simultaneously perform the nanosizing of a carbon material, the production of a metal compound precursor, the nanosizing of the metal compound precursor, and the adsorption of the metal compound precursor onto the carbon material. However, it has been found in recent research by the present inventors that even in this conventional method, more than a little aggregation of the metal compound precursor occurs before adsorption and metal compound precursors with relatively large size are adsorbed onto the carbon material, as shown in FIG. 11.